BATADV_OGM_HLEN
res = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN);
ogm_offset += BATADV_OGM_HLEN;
hard_iface->bat_iv.ogm_buff.len = BATADV_OGM_HLEN;
hard_iface->bat_iv.ogm_buff.capacity = BATADV_OGM_HLEN;
hard_iface->bat_iv.ogm_buff.header_length = BATADV_OGM_HLEN;
buff_pos += BATADV_OGM_HLEN;
BATADV_OGM_HLEN + tvlv_len,